Discharge-tube relay for undulatory currents



E. REISZ.

APPLICATION FILED JUNE 5. 1915.

1,418,022. Patented May 30,1922.

mvvvvvvi N I klizfal' Z en B60152 PATENT OFFICE.

EUG-EN REISZ, 0F TREPTOW, NEAR BERLIN, GERMANY.

DISCHARGE-TUBE RELAY F Specification 0 on UNDULATOBY CURRENTS.

fLettersPa'tent- Patented May 30,1922. Application filed June 5, 1915. Serial No. 32,437.

(GRANTED UNDER THE PROVISIONS OF THE AQT 0F MARQH 3, 1921, 41 STAT. L, 1313.)

.efiected in a vacuum tube by influencing the electric discharge between a 'Wehnelt cathode and an anode .by means of a gridlike auxiliary electrode intersecting and dividing the said tube. In relays of the said kind a great amount of electrical energy is required for the purpose of heating the Wehnelt cathode so that for this reason the volume of the tube must be a very large one.

The internal -resistance of tubes having ample superficial electrode areas and a large volume is however comparatively small, so

that in the case of large Voltages at the electrodes such as are necessary for the purpose in question, the intensity oh the discharge current that will occur will be very high. This fact will in turn give'rise to difiiculties whenever very weak currents are tobe .re-inforcd and the receiving apparatus in the-discharge circuit are to be adjusted to a great sensitivity. If abnormal variations of the tension occur" in'the primary circuit in which the currents to hereinforoed flow, then the current intensity in the secondary circuit will, in consequence of the small resistance prevailing in the discharge tube, rise to such a degree that the sensitive apparatus-connected 1nto-th1s circuit is apt to be easily damaged. It isthereforeof great advantage to augment the resistance in the discharge or secondary cir- This may be done by reducing the superficial area of he .cathode.

means the further a vantage will be gained that the materially reducedvoltage existing in the heating current will prove suflicient.

If however the amount of electrical nergy necessary to heat the cathode is reduced,

and if this reduction is carried beyond a cerof September 17, 1912, granted t'o-R. v.-

By these v stant value. Whenever therefore any considerable variation of the :voltage occurs,-

the discharge will cease and will not restart in'the course of any subsequent rise of voltage. This phenomenon is due to an in,- suflicient ionization. of that portion of the 'discharge tube which is' situated at the cathode side of the grid-like auxiliary .electrode. In relays working with high heating current voltages there reigns a. rather strong ionization in the portion of the tube situated below the auxiliary electrode, so that great variations of the voltage in the dis charge circuit even when these drop to a pointbelow, the ionization voltage of the gas or vapours in the tube will not be able toextinguish the discharge, since the ionization due to the'drop of potential caused by the heating current is sufliciently strong to be always able to restart the discharge when required.

It is the object of this invention to provide an. arrangement whereby-even when cathodes'of small area and of small heating'current voltages are employed, the ionization in the lower space of the tube (serving to contain the cathode) will be such that the discharge will always remain stable. This object is attainedby dividing the incandescent, cathode into two parts, separated by a resistance, and further by the application of the electrode voltage to these said parts, a second resistance being however interposed. By these means thereis obtained the di fierence of potentials between the two parts of the cathodereq'uired to produce a strong ionizationj In the drawing the invention is illusftrated by way of example, Each of the figures shows diagrammatically a modification of the apparatus by the aid. of whichthe object of the invention may be practically carried out.

In 1 of the drawings R is the dis- 'charge, tube; -K and K design'atethe two parts of the cathode; is the auxiliary electrode; A is the anode, and Rw, W and 1V are'the resistances. B and B are two batteries or similar sources of direct current, .adapted to supply the heating current to about 30 volts prevails between the points a and b.

For practical reasons it would prove advantageous to so select the reslstance W and R'w that their value will be comparatively large and this to the end that the value of the current intensity in the circuit embracing the source of current, the cathode and the resistances will not become too large.

All other conditions remaining the same,-

the same relay action will be obtained by the aid of a divided cathode as when a single cathode is employed; the first arrangement however necessitating only an amount of electrical energy which is from 7 to 10 times as small as that of the second arrangement. This material reduction of the heating energy furthermore permits a very considerable reduction of the volume of the discharge tube.

In the modification shown in Fig. 2, the same object is attained by arranging a cold or unheated cathode in immediate vicinity of the heated cathode. To thiscold cathode there is applied a constant but adjustable voltage, which is so chosen that between the two cathodes there will exist a difference of potential sufiicient to produce the necessary ionization in the lower discharge tube portion. This auxiliary cathode may be ofany suitable shape desired. Preferably it may be given the form of a ring or collar or of a cylinder surrounding the incandescent cathode either wholly or only in part. It will of course be understood that it is necessary to a1rrange the auxiliary cathode below the gri In Fig. 2, R is, the discharge tube; Agthe anode; G the grid-like auxiliary electrode;

K the heated cathode and H the cold auxiliary cathode'which in the present case is given an annular form. B is battery or other sourceof current adapted to heat the cathode K. Rw is a-resistance connected in between the circuit of the electrodes that likewise contain a source of current F; this last-named resistance being furthermore provided with sliding contacts E and F The contact F is connectcd'to the auxiliary cathode H and serves to apply the necessary potential thereto. From the contact F a connection leads to the transformer P of the circuit carrying the currents which are to be re-inforced, and also to the grid G. There is moreover provided a transformer S serving to'transform the re-inforced currents.

In this modification the battery B may consist of a single accumulator cell. A further advantage of this modification resides in the fact of only five conductors leading from the tube. whereas six are re uired in the case of the first-mentioned modification. Besides the introduction of the cold cathode is followed by the advantage that the gleaming or glimmering discharge takes place immediately.

As already mentioned, discharge tubes provided with electrodes of a small superficial area and having aslnall volume possessa high internal resistance, so that the intensity of the discharge current will be small. Assuming 220 volts to be the difference of voltage between the electrodes and 8 watts to-be the amount of electrical energy required to heat the cathode, then the current intensity of the anode current will only amount to a few milliamperes. If noW a higher voltage is induced in the circuit containing the cathode and the grid electrode, the relay will only re-inforce the currents up to values as are within the limits of the current intensity of the anode current. If only very small energies are present in the primary circuit, the resistance W chosen will preferably be one of a great value so as to.

reduce the current intensity of the-discharge. Insuch a case the apparatus in the secondary circuit S may be adjusted to a great sensi-' tivity, and'this without giving rise to any apprehension of the apparatus being. damaged in consequence of any unexpected variations of the voltage in the. primary circuit P. This fact is of particular importance whenever the relay is to be used inv wireless telegraphy or telephony, since the strong rushof current caused by atmospheric discharges will not in the case .under notice overload the receiving apparatus and thus imperil'the same. Further advantages will be secured in connection with portable apparatus in view of the fact that the capacity of the source of current is materially reduced.

What I 01a 1. In a re for undulatory currents comprising a discharge tube with an anode, a cathode, and grid-like auxiliary electrode between said anode and cathode dividing the relay into two separate parts, means to supply current of definite potential .to each of said electrodes, and an auxiliary cathode in the portlon of the relay containing the cathode, the potential applied to said auxiliary cathode being higher than that of the oathode but less than that of the grid-like electrode.

2. A discharge tube relay for undulatory currents, comprising an anode, a grid-like auxiliary electrode separating the discharge tube portion into two distinct parts, a cathode divided into two parts, a resistance connected in circuit between the said parts of the cathode, another resistance at the posi-,

tive end of the cathode, and means for supplying current to said parts of the cathode and to the resistances in order to produce thereby a sufficiently large difference in potential between the different parts of the cathode to cause powerful ionization within the discharge tube below the auxiliary elecother resistances are connected with the electric tensionbetween the electrodes respectively with thesource of current in such a manner that a sufliciently large difference in potential is produced between the said parts of the cathode to causepowerful ionization within the discharge tube below the auxiliary electrode.

4. A discharge tube relay for undulatory currents, comprising an anode, a grid-like auxiliary electrode separating the discharge tube portion into two distinct parts and which is arranged in the'tube between the anode and the cathode, a cathode consisting of an incandescent band or wire, which cathode is divided into two parts, these said partsbeing connected with one another by means of a resistance and being connected with another resistance, as well as with the. first-mentloned reslstance'in clrcult in such a manner as to produce a powerful lonlzation -in the discharge tube space below the grid electrode.

5. A discharge tube relay for undulatory currents, comprising an anode, a grid-like auxiliary electrode dividing the d scharge I tube space into two distinct parts and which is arranged in the tube between the anode and the cathode, a cathode consisting of anincandescent wire or band portion and an-' a other non --incandescent portion, the said portions being connected with one another by means-of a resistance, and all these parts and the resistance-being connected together with another resistance in a common circuit in sucha manner as to produce a large difference in potentialbetween the incandescent and the non-incandescent cathode portion and thus obtaining a powerful ionization in the discharge tube portion below the grid-like auxiliary electrode.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

a EUGEN REISZ. Witnesses:

ANNEMARIE REIsz, HENRY HASPERQ 

